In order to electrically connect a battery and an inverter to each other, an electrical connection box has been loaded on an electric vehicle, including a hybrid vehicle, from the related art. However, in the electrical connection box, there is a case where rattling, such as oscillation of a vehicle, is generated, and there is a concern that a terminal becomes worn out due to oscillation between a terminal of a relay and a terminal on the electrical connection box side when the rattling is generated.
Here, an electrical connection box which prevents rattling of a certain large-sized heavy relay which is mounted on a connection box main body of the electrical connection box is disclosed (refer to PTL 1).
<Electrical Connection Box Described in PTL 1>
FIG. 4 is a perspective view of a part of an electrical connection box described in PTL 1.
In FIG. 4, an electrical connection box 100 described in PTL 1 is configured of a relay 200, and a connection box main body 300 for mounting the relay 200. Here, the relay 200 and the connection box main body 300 will be briefly described.
<Relay 200>
The relay 200 is a rectangular parallelepiped object which is made of an insulating resin and which stores a relay therein.
Four male terminals 200T protrude downward from the outside of a bottom portion of the relay 200, and the four male terminals 200T are inserted into a terminal insertion hole 300T of an upper cover 310 when the relay 200 is stored in a storage space 300P of the upper cover 310.
In addition, locking projections 200K as follows are respectively formed on one side surface of the relay 200 and on a surface opposite to the side surface.
<Locking Projection 200K>
The locking projection 200K is an object having a shape of a triangular prism which is made of a perpendicular surface that stands perpendicularly from the side surface, and an inclined surface which gradually approaches the side surface downward (insertion direction) from the perpendicular surface.
When the relay 200 is stored in the storage space 300P of the upper cover 310, the locking projection 200K is engaged with an elastic locking frame piece 300K of the upper cover 310, and the relay 200 is integrated with the upper cover 310, and then with the connection box main body 300.
<Connection Box Main Body 300>
The connection box main body 300 is made of the upper cover 310 made of an insulating resin, and a lower cover 320 which is equivalently made of an insulating resin. The upper cover 310 and the lower cover 320 are integrated with each other as an elastic locking frame piece 300R which is on the upper cover 310 is engaged with a locking projection 320R which is on the lower cover 320.
<Upper Cover 310>
On the upper cover 310, four guide walls 300W for storing the rectangular parallelepiped relay 200 in the storage space 300P of the upper cover 310 are installed to stand on a surface of the upper cover 310.
<Guide Wall 300W>
Each of the guide walls 300W is L-shaped when viewed from a plan view, and is made as wall surfaces 300U and 300U which respectively extend only by a predetermined length are installed to stand along two sides at a right angle.
Four guide walls 300W are disposed at four corners along an outline of the rectangular parallelepiped relay 200 when viewed from a plan view at a predetermined interval by making each of the right angles (valley) face the inside on an upper surface of the upper cover 310. Accordingly, the storage space 300P which is surrounded by the four guide walls 300W becomes a part which stores the relay 200.
<Terminal Insertion Hole 300T>
In the storage space 300P of the upper cover 310, a plurality (four in the embodiment, but only three of these are seen in FIG. 4) of terminal insertion holes 300T are respectively formed passing through the upper cover 310.
In each of the terminal insertion holes 300T, when the relay 200 is stored in the storage space 300P of the upper cover 310, the male terminal 200T of the relay 200 is inserted, and the male terminal 200T is inserted into a female terminal on the lower cover 320 side which is installed immediately below the terminal insertion hole 300T.
<Elastic Locking Frame Piece 300K>
One guide wall 300W and a guide wall 300W which is adjacent thereto are separated at a predetermined interval, and the elastic locking frame piece 300K is installed to stand in the space between the guide walls 300W.
Equivalently, in a space on a facing side of the squared storage space 300P of the upper cover 310, one more elastic locking frame piece 300K is installed to stand.
When the relay 200 is stored in the storage space 300P of the upper cover 310, the locking projection 200K of the relay 200 is engaged with the elastic locking frame piece 300K, and the relay 200 is locked to the upper cover 310, and then to the connection box main body 300.
<Rattling Prevention Projections 300A and 300B>
On each of the L-shaped guide walls 300W, two projections 300A and 300A which extend in a horizontal direction from the inside of both upper ends toward the relay 200 when performing mounting are formed, and two projections 300B and 300B which extend in the horizontal direction from the inside of a lower bent portion toward the relay 200 when performing mounting are formed.
Regarding the height in the horizontal direction from the wall surface 300U of the projection 300A and the projection 300B, the height of the projection 300A is formed to be slightly higher than the height of the projection 300B.
<Lower Cover 320>
Although not illustrated in FIG. 4, the lower cover 320 stores the necessary number of bus bars inside thereof, and a connection terminal which is electrically connected to each bus bar and stands in an upright direction. In addition, each connection terminal is disposed immediately below the terminal insertion hole 300T of the upper cover 310 into which the male terminal 200T of the relay 200 is inserted.
The lower cover 320 is used being fixed to a vehicle body or the like, and a fixing bracket 320B is formed thereon.
<Rattling Elimination Function of Electrical Connection Box Described in PTL 1>
Next, functions of the electrical connection box described in PTL 1 will be described by using FIGS. 5 and 6.
FIG. 5 is a sectional view when viewed in a direction of an A-A arrow of the electrical connection box which has the relay of FIG. 4 mounted thereon. FIG. 6 is a plan view of the electrical connection box which has the relay of FIG. 4 mounted thereon.
In FIG. 5, the projections 300A on each upper side protrude in the horizontal direction from the inner surface of the guide wall 300W to be longer than the projections 300B on each lower side. Similarly to FIGS. 5 and 6, the projection 300A on the upper side comes into contact with relay 200 without a gap, and the projection 300B on the lower side is disposed having a slight gap S1 between the projection 300B and the relay 200. Since each guide wall 300W is narrow and high, the guide wall 300W itself has elasticity of a resin material in a direction of a plate width, and the projection 300A on the upper side elastically abuts against the relay 200 in a state where the guide wall 300W is bent slightly outward.
Meanwhile, a part on a lower end side of the guide wall 300W is unlikely to be bent, by providing the slight gap S1 between the projection 300B on the lower side and the relay 200, it is possible to reliably insert the relay 200 until the relay 200 abuts against an upper wall surface of the upper cover 310 along the projection 300B on the lower side. When the relay 200 moves due to oscillation, the projection 300B on the lower side has a function of coming into contact with an outer wall surface of the relay 200 and preventing the oscillation and vibration.
As one pair of projections 300A on the upper side are disposed on both sides of the guide wall 300W, it is possible to stably support the outer wall surface of the relay 200 in the horizontal direction.
<Points to Overcome in Electrical Connection Box Described in PTL 1>
Locking the relay 200 and the connection box main body 300 to each other is achieved by engaging the elastic locking frame piece 300K which is provided to stand in a space between the guide wall 300W and the adjacent guide wall 300W, and the locking projection 200K which is formed on the side surface of the relay 200.